Equipment within telecommunication networks provide redundant or sparing techniques to ensure that information is transferred despite a failure in any other part of the equipment. Typically, telecommunication devices receive signal information at a splitter that provides outputs to a primary signal path and a spare signal path. A splitter is an analog passive device that generates two copies of a signal having a lower amplitude and similar impedance as the original signal. The splitter receives a control signal that determines which transmission path will carry the input signal information. Signal information is carried over the primary transmission path unless a failure occurs along the primary transmission path. Alternatives to a splitter include a router, a relay, or a switch.
When a failure is detected, the splitter routes the signal information to the spare transmission path in response to the control signal. However, the splitter and its alternatives are not a very reliable approach in that there is access to only one path and a break or an interruption of the input signal information occurs when switching from one signal path to another. Monitoring of the actual signal being received by a telecommunications device is difficult in a splitter environment and testing cannot be performed on the actual input signal information being received by the telecommunications device. Therefore, it is desirable to have a sparing technique that does not cause a break in the transmission path of the signal information being received.
From the foregoing, it may be appreciated that a need has arisen for a sparing technique that does not interrupt the transmission path of the incoming signal. A need has also arisen for a sparing technique that allows for monitoring of the actual signal being received. Further, a need has arisen for a sparing technique that can perform diagnostic operations on the actual signal being received.